Structure of a cooling fan

ABSTRACT

A cooling fan structure comprises a base and a ring stator mounted in the center of the base such that a plurality of polar claws are bent to form in the inner side of the ring stator in conjunction with a plastic material. A coil is wound in the outer side of the ring stator. A blade rotor seat is mounted in the base such that the blade rotor seat circumvents the ring stator. A magnetic ring rotor is mounted on an axis in the receiving space of the ring stator such that the magnetic ring rotor is induced by the coil of the ring stator to drive the blades.

RELATED U.S. APPLICATIONS

[0001] Not applicable.

STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT

[0002] Not applicable.

REFERENCE TO MICROFICHE APPENDIX

[0003] Not applicable.

FIELD OF THE INVENTION

[0004] The present invention relates generally to a cooling device, and more particularly to a cooling fan structure which is simple in construction, and efficient in driving torque and ventilation.

BACKGROUND OF THE INVENTION

[0005] As shown in FIGS. 1-3, a prior art cooling fan structure comprises a base 11, which is provided in the center with a stator 12. The stator 12 is formed of a plurality of coils 13 and polar bars 14 on which the coils 13 are wound. A plurality of blades 16 are fastened with a rotor seat 17 which is provided in the inner edge with a magnetic ring rotor 18. The magnetic ring rotor 18 is induced by the coils 13 of the stator 12 to drive the blades 16. The prior art cooling fan structure is defective in design in that the winding is difficult and time-consuming, thereby resulting in high rejection rate of the product.

[0006] As shown in FIGS. 4-6, another prior art cooling fan structure comprises a base 21 and a stator 22 which is mounted in the center of the base 21 and is formed of a coil 23. The coil 23 is circumvented by an upper polar piece 24 and a lower polar piece 25 in conjunction with a magnetically permeable tube 29. A plurality of blades 26 are fastened with a rotor seat 27 which is provided in the inner side with a magnetic ring rotor 28. The magnetic ring rotor 28 is induced by the coil 23 of the stator 22 to drive the blades 26. The coil 23 is vulnerable to damage in the course of mounting the upper polar piece 24 and the lower polar piece 25, thereby resulting in high rejection rate of the product.

[0007] These two prior art cooling fan structures share a common limitation. The pole number and the phase number of the stators 12 and 22 cannot be easily increased. In addition, they have a dead point problem, which prevents their operational stability from being effectively enhanced.

BRIEF SUMMARY OF THE INVENTION

[0008] It is the primary objective of the present invention to provide a cooling fan structure comprising a ring stator having a coil and being mounted in the center of a base. The structure further comprises a magnetic ring rotor which is mounted on an axis of a blade rotor seat. As a result, the winding of the structure of the present invention is simplified.

[0009] It is another objective of the present invention to provide a cooling fan structure comprising a ring stator and a magnetic ring rotor. The ring stator is mounted in the center of a base, while the magnetic ring rotor is mounted on an axis of a blade rotor seat. As a result, the pole number of the ring stator can be easily increased to enhance the operating stability of the cooling fan structure.

[0010] It is still another objective of the present invention to provide a cooling fan structure comprising two sets of ring stators and two sets of coil. The ring stator is provided with a plurality of polar pieces, which are fastened with a ring seat along with an insulation plastic material, so as to facilitate the winding of the coil. As a result, the operational dead point of the structure of this present invention is eliminated.

[0011] The features, functions, and advantages of the present invention will be more readily understood upon a thoughtful deliberation of the following detailed description of two preferred embodiments of the present invention with reference to the accompanying drawings.

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS

[0012]FIG. 1 shows an exploded view of a cooling fan structure of the prior art.

[0013]FIG. 2 shows a top plan view of the prior art cooling fan structure in combination.

[0014]FIG. 3 shows a sectional schematic view of the prior art cooling fan structure in combination.

[0015]FIG. 4 shows an exploded view of another prior art cooling fan structure.

[0016]FIG. 5 shows a top plan view of the another prior art cooling fan structure in combination.

[0017]FIG. 6 shows a sectional schematic view of the another prior art cooling fan structure in combination.

[0018]FIG. 7 shows a perspective view of a first preferred embodiment of the present invention.

[0019]FIG. 8 shows an exploded view of the first preferred embodiment of the present invention.

[0020]FIG. 9 shows a sectional schematic view of the first preferred embodiment of the present invention in combination.

[0021]FIG. 10 show an exploded view of a second preferred embodiment of the present invention.

[0022]FIG. 11 shows a sectional schematic view of the second preferred embodiment of the present invention in combination.

DETAILED DESCRIPTION OF THE INVENTION

[0023] As shown in FIGS. 7-9, a cooling fan structure of the first preferred embodiment of the present invention comprises a base 31, a ring stator 32, a blade rotor seat 37, and a magnetic ring rotor 38.

[0024] The ring stator 32 is mounted in the center of the base 31 and is formed of a plurality of polar claws 34 and a coil 33. The polar claws 34 are disposed in the inner side of the ring stator 32 and are integrally made of a plastic material with the ring stator 32. The coil 33 is wound around the outer side of the ring stator 32.

[0025] The blade rotor seat 37 is mounted in the base 31 such that the blade rotor seat 37 circumvents the ring stator 32. The blade rotor seat 37 is fastened with a plurality of blades 36.

[0026] The magnetic ring rotor 38 is disposed in a receiving space of the ring stator 32 and is mounted on an axis 39. The magnetic ring rotor 38 is induced by the coil 33 of the ring stator 32 to drive the blades 36.

[0027] As shown in FIGS. 10 and 11, the ring stator 32 of the second preferred embodiment of the present invention is formed of two sets of polar claws 34 and two sets of coil 33, so as to increase the pole number of the ring stator 32. As a result, the operational stability of the cooling fan structure of the present invention is enhanced. In light of alternate layout of the phase number, the operational dead point of the present invention is eliminated to enhance further the operational stability of the present invention. The polar claws 34 are disposed in the inner side of the ring stator 32, while the coils 33 are wound on the outer side of the ring stator 32. As a result, the winding of the present invention is simplified to reduce the rejection rate of the product. In light of the structure of the present invention being provided with a plural sets of the polar claws 34, the operational stability of the present invention is further enhanced. In the meantime, the dead point problem is eliminated.

[0028] The embodiments of the present invention described above are to be regarded in all respects as being illustrative and nonrestrictive. Accordingly, the present invention may be embodied in other specific forms without deviating from the spirit thereof. The present invention is therefore to be limited only by the scope of the following claims. 

I claim:
 1. A cooling fan structure comprising: a base; a ring stator mounted in a center of the base and formed of a plurality of polar claws and a coil, with said polar claws being disposed in an inner side of said ring stator and being made integrally of a plastic material with said ring stator, said coil being wound around an outer side of said ring stator; a blade rotor seat provided with a plurality of blades fastened therewith, said blade rotor seat being mounted in said base such that said blade rotor seat circumvents said ring stator; and a magnetic ring rotor mounted on an axis in a receiving space of said ring stator such that said magnetic ring rotor is induced by said coil of said ring stator to drive said blades.
 2. The cooling fan structure as defined in claim 1, wherein said polar claws of said ring stator are arranged in a plurality of pole numbers.
 3. The cooling fan structure as defined in claim 1, wherein said ring stator and said coil are arranged in two sets to form an upper set and a lower set.
 4. The cooling fan structure as defined in claim 3, wherein said polar claws of each ring stator are made integrally of an insulation plastic material as a ring seat for locating each coil. 